Product Description:

The E4809-436-032A memory module is produced by Okuma for the E4809 CNC Boards series. It works as an internal expansion card that stores machining programs and system parameters directly inside an Okuma numerical control. By keeping data on the control backplane instead of on removable media, the board supports uninterrupted tool path execution and short program load times in an automated production environment. The control recognizes the card during power-on self-test and treats it as part of the base memory map. Because the memory stays on the control bus, the module remains available whenever the CNC starts and does not depend on external media connections.

Its storage medium is DRAM, so read and write cycles occur at the bus clock rate without mechanical delay. This helps the control retrieve and update data without seek time or spindle latency. The control identifies the module by the card designation MC 12, a revision code aligned with the timing and voltage requirements of the E4809 bus. Total installed capacity is 2 Mbyte, giving additional space for large conversational programs or probe routines. CPU access uses One Card Type, meaning the central processor maps the full two-megabyte block as one contiguous memory area, which simplifies address decoding. Mechanical installation is through the backplane slot on the MB-IIB motherboard, where the edge connector carries the address lines and regulated supply rails.

A maximum of 3 identical cards can be fitted on a single MB-IIB backplane. Mixing MC11 and MC12 variants is not permitted, so every populated slot must use an MC12 module to avoid bus contention. Classified as a Memory Card, the module contains no active processing logic and receives all control signals from the host board. The arrangement leaves all processing tasks to the CNC motherboard, while the add-in card serves only as memory expansion.